1. Field of the Invention
The present invention relates to a network system, and more particularly to a network system which controls communication over Internet Protocol (IP) networks including a mobile domain.
2. Description of the Related Art
The rapid advancement of the Internet infrastructures in recent years has brought about increasingly high IP packet traffic. Stimulated by the proliferation of cellular telephones, the development of high-speed IP-based mobile communication environments is making considerable progress. It is also expected that the standardization and deployment of the International Mobile Telecommunications 2000 (IMT2000) specifications will accelerate these development trends. Such innovations have fueled the demands for more sophisticated IP services, including the provision of differentiated quality of service (QoS) classes for individual users, and the network-wide load distribution for WWW servers. The technological basis for those value-added services, however, has not yet been matured enough. To make the highly sophisticated services possible, it is necessary to develop several new techniques described below.
One of the demanded features for future mobile communication systems is a control mechanism that dynamically updates service control data (service profiles) according to various conditions and administrative policies. While it may be similar to what is implemented in the existing telephone networks, as in the Intelligent Network (IN) service, this feature is available in conventional mobile communication systems.
Another demand is related to how to make a profit in the Internet service business, under the pressure of gradual price reduction in the market of access networks. Seeking solutions, the telephone carriers and Internet service providers (ISPs) tend to shift their business to more application-specific, value-added service areas. The users, on the other hand, have their primary interests in gaining the best quality of service while paying less money. The problem is, however, that the quality of service is traffic load dependent. Even if a person subscribes to an expensive, high-quality communication service, he/she is merely paying extra money for the same service quality as other ordinary customers may receive, when the network is a low-traffic condition. In other words, it is difficult, in such low-traffic situations, for the telecom carriers and ISPs to boost their profits by providing different rate options.
For the above reason, a simple high QoS option is no longer an attractive feature for such Internet users who connect only in low-traffic time periods. In actuality, the best combination of QoS and price for one customer is not necessarily the best thing for other customers. Obviously, a plain old service menu will not work. It is rather necessary to develop a new service product that can be customized to meet the need of each individual customer, taking into consideration his/her life style, network usage patterns, and affordable costs. In addition to those requirements, such services have to be dynamically reconfigured even in the middle of a communication session over Mobile IP networks.